TY  - RPRT
TI  - Trace element geochemistry of altered volcanic ash layers (tonsteins) in late Permian coal-bearing formations of eastern Yunnan and western Guizhou Provinces, China
AU  - Y. Zhou
AU  - B.F. Bohor
AU  - Y. Ren
PY  - 2000
DO  - 10.1016/s0166-5162(00)00017-3
UR  - https://pubs.usgs.gov/publication/70022514
ID  - 70022514
ER  -